The present invention relates to a semiconductor device with trench type capacitors and, more particularly, to the capacitor structure in the logic circuit portion of a DRAM/logic embedded integrated circuit.
In a conventional embedded integrated circuit in which a DRAM and a logic circuit such as MPU or the like, are mixedly disposed, the capacitors provided in the logic circuit portion are realized by the use of planar type capacitors structure. It is because, though trench type capacitors are used in the memory cells in the DRAM portion, the capacitance value thereof is small, so that they are not practically suitable for use in the logic circuit portion.
However, if planar type capacitors are used in the logic circuit portion in order to realize a desired magnitude of capacitance such as, e.g. the power supply stabilization capacitance of a stabilized power supply circuit, then the pattern area occupied by the capacitors becomes large, so that the degree of freedom in the circuit design lowers.
Further, in the case of the conventional DRAM/logic embedded integrated circuit, if the capacitance value of the capacitors is to be altered in the logic circuit portion as required in view of the circuit design from chip to chip, then the manufacturing steps must be altered, the chip-wise alteration is thus difficult.